<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>3_回调ref中回调执行次数的问题</title>
</head>

<body>
  <!-- 准备好一个“容器” -->
  <div id="test"></div>

  <!-- 引入react核心库 -->
  <script type="text/javascript" src="../js/react.development.js"></script>
  <!-- 引入react-dom，用于支持react操作DOM -->
  <script type="text/javascript" src="../js/react-dom.development.js"></script>
  <!-- 引入babel，用于将jsx转为js -->
  <script type="text/javascript" src="../js/babel.min.js"></script>

  <!-- 此处一定要写babel -->
  <script type="text/babel">
    // 1. 创建组件
    class MyComponent extends React.Component {

      state = {
        isHot: true,
        wind: '微风'
      }

      changeWeather = () => {
        const isHot = this.state.isHot
        this.setState({
          isHot: !isHot
        })
      }

      // 展示左侧输入框的数据
      showData = () => {
        const {input1} = this
        console.log(input1.value)
      }

      saveInput = currentNode=> {
        this.input1 = currentNode;console.log('@', currentNode)
      }

      render() {
        const {isHot, wind} = this.state
        return (
          <div>
            <h1>今天天气很{isHot ? '炎热':'凉爽'},{wind}</h1>
            {/*<input ref={currentNode=> {this.input1 = currentNode;console.log('@', currentNode)}} type="text" placeholder="点击按钮提示数据" />*/}
            <input ref={this.saveInput} type="text" placeholder="点击按钮提示数据" />
            &nbsp;<button ref="button" onClick={this.showData}>点我提示输入的数据</button>
            &nbsp;<button onClick={this.changeWeather}>点我切换天气</button><br/>
          </div>
        )
      }
    }
    // 2. 渲染组件到页面
    ReactDOM.render(<MyComponent />, document.getElementById('test'))
  </script>
</body>

</html>